<?php

namespace Aws\S3;

use Aws\CommandInterface;
use Aws\Multipart\UploadState;
use Aws\ResultInterface;

trait MultipartUploadingTrait {
	/**
	 * Creates an UploadState object for a multipart upload by querying the
	 * service for the specified upload's information.
	 *
	 * @param S3ClientInterface $client S3Client used for the upload.
	 * @param string $bucket Bucket for the multipart upload.
	 * @param string $key Object key for the multipart upload.
	 * @param string $uploadId Upload ID for the multipart upload.
	 *
	 * @return UploadState
	 */
	public static function getStateFromService(
		S3ClientInterface $client,
		                  $bucket,
		                  $key,
		                  $uploadId
	) {
		$state = new UploadState([
			'Bucket' => $bucket,
			'Key' => $key,
			'UploadId' => $uploadId,
		]);

		foreach($client->getPaginator('ListParts', $state->getId()) as $result) {
			// Get the part size from the first part in the first result.
			if(!$state->getPartSize()) {
				$state->setPartSize($result->search('Parts[0].Size'));
			}
			// Mark all the parts returned by ListParts as uploaded.
			foreach($result['Parts'] as $part) {
				$state->markPartAsUploaded($part['PartNumber'], [
					'PartNumber' => $part['PartNumber'],
					'ETag' => $part['ETag']
				]);
			}
		}

		$state->setStatus(UploadState::INITIATED);

		return $state;
	}

	protected function handleResult(CommandInterface $command, ResultInterface $result) {
		$this->getState()->markPartAsUploaded($command['PartNumber'], [
			'PartNumber' => $command['PartNumber'],
			'ETag' => $this->extractETag($result),
		]);
	}

	abstract protected function extractETag(ResultInterface $result);

	protected function getCompleteParams() {
		$config = $this->getConfig();
		$params = isset($config['params']) ? $config['params'] : [];

		$params['MultipartUpload'] = [
			'Parts' => $this->getState()->getUploadedParts()
		];

		return $params;
	}

	protected function determinePartSize() {
		// Make sure the part size is set.
		$partSize = $this->getConfig()['part_size'] ?: MultipartUploader::PART_MIN_SIZE;

		// Adjust the part size to be larger for known, x-large uploads.
		if($sourceSize = $this->getSourceSize()) {
			$partSize = (int)max(
				$partSize,
				ceil($sourceSize / MultipartUploader::PART_MAX_NUM)
			);
		}

		// Ensure that the part size follows the rules: 5 MB <= size <= 5 GB.
		if($partSize < MultipartUploader::PART_MIN_SIZE || $partSize > MultipartUploader::PART_MAX_SIZE) {
			throw new \InvalidArgumentException('The part size must be no less '
				.'than 5 MB and no greater than 5 GB.');
		}

		return $partSize;
	}

	protected function getInitiateParams() {
		$config = $this->getConfig();
		$params = isset($config['params']) ? $config['params'] : [];

		if(isset($config['acl'])) {
			$params['ACL'] = $config['acl'];
		}

		// Set the ContentType if not already present
		if(empty($params['ContentType']) && $type = $this->getSourceMimeType()) {
			$params['ContentType'] = $type;
		}

		return $params;
	}

	/**
	 * @return UploadState
	 */
	abstract protected function getState();

	/**
	 * @return array
	 */
	abstract protected function getConfig();

	/**
	 * @return int
	 */
	abstract protected function getSourceSize();

	/**
	 * @return string|null
	 */
	abstract protected function getSourceMimeType();
}
